A former campaign aide to Donald Trump who sought to secure a meeting between the future US president and Vladimir Putin has pleaded guilty to lying to federal agents working for special counsel Robert Mueller as part of his investigation into possible coordination between the Trump campaign and Russia.

A former campaign aide to Donald Trump who sought to secure a meeting between the future US president and Vladimir Putin has pleaded guilty to lying to federal agents working for special counsel Robert Mueller as part of his investigation into possible coordination between the Trump campaign and Russia.